Sharp 29A-SX1, Service Manual

Page: 4 / 86

4
29A-SX1
29A-SX5
29A-SX8
SX-68JF200
4
IMPO
T
ANT SER
VICE NO
TES
Maintenance and repair of this receiver should be done by qualified ser
vice per
onnel onl
y
.
SER
VICING OF HIGH
V
O
L
T
A
GE SYSTEM AND
PICTURE TUBE
When servicing the high voltage system, remove static charge from it by connecting a 10k ohm Resistor in series with an insulated wire (such as a test probe) between picture tube dag and 2nd anode lead. (AC line cor
d should be disconnected fr
om A
C
outlet.)
1.
Picture tube in this receiver employs integral implosion protection.
2.
Replace with tube of the same type n
umber f
or contin
ued safety
.
3.
Do not lift picture tube by the neck.
4.
Handle the picture tube only when wearing shatterproof goggles and after dis- char
ging the high v
olta
g
e
completel
y
.
X-RA
Y
This receiver is designed so that any X-Ray radiation is kept to an ab- solute minimum. Since certain malfunctions or servicing many pro- duce potentially hazardous radiation with prolonged exposure at close range, the following precautions should be observed:
1.
When repairing the cir
cuit,
be sure not to increase the high v
olta
g
e
to more than
33.0 kV (at beam 0
µ
A) f
or the set.
2.
T
o
keep the set in a normal operation,
be sure to make it function on 29.5
±
1.5kV
(at beam 1.7 mA) in the case of the set.
The set has been factory-Adjusted to the
above mentioned high voltage.
If there is a possibility that the high v
olta
g
e
fluctuates as a result of repair
s,
ne
ver f
o
rget to chec
k f
or suc
h high v
oltage after the w
ork.
3.
Do not substitute a picture tube with unauthorized types and/or brands whic
h ma
y
cause e
xcess X-Ra
y radiation.
BEFORE RETURNING THE RECEIVER
Bef
ore returning the receiver to the user
, perf
orm the f
ollo
wing saf
ety
checks.
1.
Inspect all lead dress to make certain that the leads are not pinched or that hardware is not lodg
ed between the c
hassis and other metal par
ts in the receiver
.
2
.
Inspect all pr
otective de
vices suc
h as non-metallic contr
ol knobs,
insulating
fishpapers,
cabinet backs, adjustment and compartment covers or shields, iso-
lation resistor- capacity networks, mechanical insulators etc.